Forest yield in relation to forest tending. Should the principles of forest tending be changed?
1997
Kotar, M. (Ljubljana Univ. (Slovenia). Biotechnical Fac., Forestry Dept.)
The article deals with the possibilities of the rationalization of forest tending. The emphasis has been placed on thinnings which accompany the growth and development of forest during the prevalent part of its production period. A comparison of the effects and costs of selective thinnings, established by Schaedelin and Leibundgut in Switzerland, has been made with those developed by Abetz in Germany. The former achieve their goals through selected trees, the number of which successively decreases with every new thinning until only final selected trees remain in the stand and possibly those with a serving role. The thinning according to Abetz achieves its objectives with crop-trees, the number of which is constant from pole stand to large timber, i.e. until the regeneration of a stand. As to the achieving of timber production and other nonproduction goals the selective thinning, based on selected trees, has advantage over the other method
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